This invention relates generally to aircraft aerodynamics and specifically to a method and apparatus for attenuating the airstream vortex generated at the wingtips of aircraft.
The lift-induced wingtip vortex associated with large jet aircraft has become a major problem to the air traffic controller as well as an unseen hazard to smaller aircraft. The problem arises from the fact that the vortex created by large aircraft is very strong and of such long persistence and that it intensifies as the weight of the aircraft increases. The rotational airflow or vortex developed at or near the wingtip of an aircraft remains essentially stationary in space and induces a rolling moment on smaller following aircraft if encountered. This rolling moment can be so strong that it surpasses the limits of control of the smaller aircraft and such loss of control has been proven to occur as far as 4 miles behind a large aircraft. The vortex problem is particularly severe in flight paths around major airports where smaller aircraft are most likely to follow large aircraft and where the small aircraft has little altitude in which to regain control.
Previous attempts to limit the vortex effect have generally been unsuccessful either because, as with wing end plates or wingtip extensions, the devices did not sufficiently modify the far downstream effects of the vortex or, as with landing flap variations and wing spoilers, the vortex attenuation caused too great a lift loss for the aircraft.